Answer:
Moles = 0.271 mol
Solution:
Step 1: Calculate Mass of Br₂ as;
Density = Mass ÷ Volume
Solving for Mass,
Mass = Density × Volume
Putting values,
Mass = 3.12 g.mL⁻¹ × 13.9 mL
Mass = 43.36 g
Step 2: Calculate Moles of Br₂ as;
Moles = Mass ÷ M.Mass
Putting values,
Moles = 43.36 g ÷ 159.80 g.mol⁻¹
Moles = 0.271 mol